Conventionally, known is server virtualization technology of building a plurality of virtual servers (hereinafter referred to as the “virtual servers”) in one physical server. As a result of using this kind of server virtualization technology, it is possible to consolidate a plurality of physical servers and improve the usage efficiency of resources.
As one method of realizing the practical application of this kind of server virtualization technology, conventionally, a sharing method of a plurality of virtual servers sharing resources such as a CPU, memory and I/O (input/output) device of one physical server, and assigning the necessary resource to the virtual server as needed has been proposed (for example, refer to PTL 1 and NPL 1).
Moreover, as another method of realizing the practical application of the server virtualization technology, a logical partitioning method of dividing resources such as a CPU, memory and I/O (input/output) device of one physical server into a plurality of logical partitions (these correspond to the virtual servers and are hereinafter referred to as the “logical partitions”) has also been proposed (for example, refer to NPL 2).